Pager Demodulator Log plugin

Introduction

This plugin is a logging-focused fork of SDRangel’s Pager Demodulator.

It demodulates POCSAG pager messages and adds SQLite logging controls, block-list filters, and “human-readable” tagging via regex or a dictionary.

Multiple instances of the plugin can write on the same SQlite DB simultaneously.

Quick install

1. Download PagerDemodLog-7.22.8-Qt6.7.3-msvc2022-x64.zip.

2. Unzip into your SDRangel install folder (where SDRangel.exe is).

Final layout:
     - SDRangel folder/
         - SDRangel.exe
         - Qt6Sql.dll                 
         - plugins/
             - demodpagerlog.dll
         - sqldrivers/
             - qsqlite.dll

3. Start SDRangel → Add channel → “Pager Demodulator Log”.

If DB logging doesn’t work:

• Ensure sqldrivers/qsqlite.dll exists next to SDRangel.exe.
• Versions must match (SDRangel 7.22.8 & Qt 6.7.3 & MSVC 2022-x64).

Interface

The top and bottom bars of the channel window are described here.

1: Filter duplicates

Toggle duplicate filtering. Right-click for options (match adresses and messages by default, options to match message only and last only). Duplicate filtering affects logging coherently (CSV and DB).

2: Notifications

Opens the notifications dialog (highlighting, speech/command actions, map plotting).

3: Start/Stop recording

Single button that starts/stops logging for both CSV and SQLite backends (subject to each backend’s “Use …” checkbox below).

4: Only log human-readable

Two checkboxes:

• Only log human readable to CSV
• Only log human readable to DB

When enabled the row is logged only if a human-readable tag is detected (see sections 7-8).

5: Use CSV + path

Enable/disable CSV logging and choose the output file path.

CSV columns match the table: Date, Time, Address, Function Bits, Alpha, Numeric, Even Parity Errors, BCH Parity Errors.

6: Use SQLite + path

Enable/disable SQLite logging and choose a database file path. See schema in the SQLite section below.

7: Custom regex

A multi-line list of QRegularExpression patterns used to tag messages as human-readable.

The header row includes an Enable custom regex checkbox.

If a line starts with label: the label is stored in the DB tag.

Examples:

• phone_e164:^+[1-9][0-9]{5,14}$
• phone: (?:(?<!\d)0(?:[1-9])(?:[ .-]?\d{2}){4}(?!\d)|(?<!\d)0\d{9}(?!\d))
• date: (?<!\d)(?:\d{2}[.-/ ]\d{2}[.-/ ]\d{4}|\d{4}[.-/ ]\d{2}[.-/ ]\d{2})(?!\d)

8: Dictionary detection

Enable dictionary, select a text file (one token per line), and set:

• Min word len: minimum token length
• Min word count: minimum number of distinct tokens found to tag a message

Dictionary matching is accent-insensitive and uses lower-cased tokens.

9: Block log filters (one per line)

Rules to block logging to CSV and DB before writing.

These do not affect display in "Received Messages".

Format: ADDRESS:MESSAGE with keywords:

• ALL: match any
• EMPTY: empty message

Examples:

0000001:ALL     # block all messages from address 0000001 
ALL:EMPTY       # block empty messages from any address 
0001234:Test    # block if displayed message equals "Test" for address 0001234 

A master checkbox Enable block filters turns this feature on/off.

10: Received Messages table

Columns:

• Date, Time, Address, Message, Function, Alpha, Numeric, Even PE, BCH PE

Rows are highlighted in green if a human-readable tag is detected by regex/dictionary.

Logging behavior

• Start/Stop recording applies to both CSV and DB (if their “Use …” checkbox is enabled).
• Block list is applied before logging and affects CSV and DB identically.
• Duplicate filtering can skip logging duplicates (consistent across CSV/DB).
• Only human-readable (CSV/DB) logs rows only when a non-empty tag is detected.

SQLite

The database is created if missing with WAL journaling for responsiveness. Table schema:

 CREATE TABLE IF NOT EXISTS pocsag_messages (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  date TEXT NOT NULL, time TEXT NOT NULL,
  address INTEGER NOT NULL,
  function_bits INTEGER NOT NULL,
  alpha TEXT,
  numeric TEXT,
  even_pe INTEGER,
  bch_pe INTEGER,
  readable_tag TEXT,-- e.g. 'alpha:regex:phone_fr' or 'alpha:dict:3' 
  rx_hz INTEGER, -- capture frequency (center + offset) 
  created_at TEXT DEFAULT CURRENT_TIMESTAMP ); 

Windows runtime note

Ensure Qt’s SQLite driver is deployed alongside SDRangel:

<SDRangel.exe>/sqldrivers/qsqlite.dll

Without it, the GUI will load but DB writes will not occur.

Build

This plugin is designed to be built in-tree with SDRangel.

Prerequisites

Qt 6 (Widgets/Core/SQL), CMake ≥ 3.16, C++17 compiler, SDRangel source tree.

Location

Place sources under:

sdrangel/plugins/channelrx/demodpager_log/

Targets

• GUI plugin: demodpagerlog

Notes

• Regex are Qt QRegularExpression (case-insensitive by default).
• Dictionary matching is accent-insensitive on lower-cased tokens.

Credits & license

This is a fork of SDRangel’s Pager Demodulator. Copyrights remain with their respective owners. License: GPLv3, same as SDRangel.